Dear Monks, using the following code: 
open(FILE,"textfile.txt");
while(1)
    {
    $line=<FILE>||last;
    @line=split("\t",$line);
    $last=0;
    if($line[0]ne$previous_value)
        {
        # do something
        $last=1
        }
    elsif($line[1]>=1)
        {
        # do something
        }
    $previous_value=$line[0];
    if($last==1)
        {
        seek(MAP,-length$line,1);
        last;
        }
    }
close FILE;
exit;

[download]
will I obtain different results for (length $line) when I use files that come from linux and windows machines (newline vs. form feed and carriage return?)

I want to go back one line while reading a file if a certain condition is true. Will this code work on linux and windows machines using files from a different OS?

In reply to different length of a line from linux and windows textfile? by Microcebus

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